Provenance

Reference data from EU CLP Annex VI and published regulations — verify against your supplier's SDS before use.

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Substance profile

1,3-propylene oxide

1,3-propylene oxide is an oil with an agreeable aromatic odor.

CAS 503-30-0 C3H6O 58.08 g/mol Danger

01 · Identification

What 1,3-propylene oxide is

1,3-propylene oxide is an oil with an agreeable aromatic odor. Its molecular formula is C3H6O and its molecular weight is 58.08 g/mol. It boils at 48 °C.

Under the GHS it carries the signal word Danger.

CAS number503-30-0
EC number207-964-3
Index number603-058-00-0
Molecular formulaC3H6O
Molecular weight58.08 g/mol

02 · GHS classification

Hazards and label elements

Harmonised classification under CLP Annex VI. This is the legally binding classification in the EU; other jurisdictions may differ.

Signal wordDanger
Hazard statements assigned to 1,3-propylene oxide
CodeHazard statement
H225 Highly flammable liquid and vapour.
H332 Harmful if inhaled.
H312 Harmful in contact with skin.
H302 Harmful if swallowed.

Precautionary statements: P210, P233, P241, P242, P260, P270, P271, P280, P301, P302, P304, P312, P330, P352, P403

03 · Physical and chemical properties

1,3-propylene oxide properties

Every value is shown with the conditions it was measured under and the source it came from. Where sources disagree, all values are listed rather than one being picked — the difference is usually a different form of the substance, not an error.

Property Value Conditions Source
Boiling point 48 °C (118.4 °F) at 750 mmHg HSDB
50 °C (122 °F) at 760 mmHg CAMEO
Density 0.893 g/cm³ at 25 °C HSDB
Solubility SOL IN ALL PROPORTIONS OF WATER, ALCOHOL; SOL IN ETHER; VERY SOL IN ACETONE, ORGANIC SOLVENTS HSDB
In water, miscible. HSDB
10 to 50 mg/mL at 68 °F (NTP, 1992) at 20 °C CAMEO
Vapor pressure 324 mmHg at 25 °C HSDB
324 mmHg Haz-Map
Flash point -28.33 °C (-19 °F) CAMEO
-28 °C (-18.4 °F) Haz-Map

Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.

04 · Handling and storage

Storing and handling 1,3-propylene oxide

Incompatible materials

Strained ring oxygen heterocycles such as epoxides and exetanes react with the oxide in dichloromethane at sub-ambient temperatures to form high yields of the powerfully explosive glycol dinitrate esters.

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

1,3-PROPYLENE OXIDE reacts with Grignard reagents and organolithium compounds. It is also incompatible with oxidizing agents and strong acids. (NTP, 1992). An explosion occurred when propylene oxide was added to epoxy resin. Polymerization was catalyzed by amine accelerator in the resin [Bretherick 1995]. Propylene oxide and sodium hydroxide base-catalyzed the polymerization of the former, causing ignition and explosion of a drum of the crude product. [Combust Sci. Technol., 1983].

Source: CAMEO Chemicals

Planning storage for a mix of chemicals? Check 1,3-propylene oxide in the storage compatibility matrix →

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